TL:DR - Looking for ideas to safely charge the PW battery while it is still in the vehicle. I want to prevent overcharging, preferably hook it up directly to to a 120 VAC outlet, and preferable not modify the vehicle to an extent that a warranty claim is void.

* I may be over complicating matters by not understanding some fundamentals, so please bear with me *

I just bought (haven't received yet) a Power Wheels Dune Racer Extreme (12V) for my 2 kids (almost 3 and almost 6).
I was a deprived child and have never had one myself or really ever had any experience with one other than seeing older ones rotting in the backyard of some friends or relatives. Since we will be unboxing the Dune Racer this holiday season I started investigating how these things work which let me to your awesome site here.

I see two huge issues with how these vehicles seem to be setup to charge, and I wanted confirmation of my suspicions as well as some (hopefully detailed) advice on how I can make some type of modification to make life easier.

Issue #1 - Battery must be charged ~14 hours / use and no more than 30 hours. This is according to the online manual.
The problem here is I will ultimately forget and leave the battery plugged in for more than this time (30 hrs), which will likely severely impact the batteries' life.

Issue #2 - The battery must be removed from the vehicle to charge. Maybe this isn't the case, but all the pictures, instructions I can find show people removing this from the vehicle and plugging it into a wall outlet with the included charger.
The problem here is simply the time/hassle it takes to do this.

I have spent the past hour or so investigating but am surprised I haven't found more direct answers as I would expect many people would want a solution that simply allows you to plug the car directly into an outlet and just leave it there for days/weeks on end.

I would think I need a float charger at the very least, but am unsure how this can be used/modified to plug directly into PW battery while even better keeping the battery in the vehicle.

I just found out about the Schumacher CR-1 may be the easiest (and possible very cost effective option)?

The charger has detachable dongles for each battery type and so it might be possible to leave the dongle plugged inside the battery compartment.

The Dune Racer model actually seems fairly simple in how it houses the battery:

So, worst case scenario (little effort but 80% of results), I just open the battery door, remove the motor harness and plug in the CR-1.

How could I alter this (or use another method) to reach 100% of my goals.
I would think there is someway for me to wire a dongle to mount right outside the battery compartment that would allow me to plug the CR-1 (or another charger) right in.

The big problem to me seems that you would need to keep the PW motor harness plug in and have that feed to both the PW and the charger simultaneously which means some type of toggle switch?

You will find out soon enough that the original battery will not be enough for your kids to play with. Eventually you will need to buy more batteries for extended play. Most of us here use non-pw brand battery to get a longer run time out of these cars since they are cheaper (1 pw battery price can buy 2 after market batteries with longer run time). Consider yourself this too when the time comes for your kids to scream - "dad, I wanna go faster"

Here is one way to directly charge the battery with a charge port:
FWIW, you can buy or salvage the stock battery connector like this one and mod it to have a Y connection where one will go directly to the battery and then split out 2 connections which one goes to the car and one you can use to directly plug to the charger (not sure if this will work since i have never done this before). You need to drill a hole somewhere to install the charger port which I don't know if it will void the warranty or not also.

Maybe someone here who has done similar to what you are looking for can guide you through it. I have 3 dune racers myself and I modded them out since my kids always want more features add to their cars.

lexx0116 wrote:You will find out soon enough that the original battery will not be enough for your kids to play with.

Thanks for the reply.

Yes total runtime for the two kids is a concern. Additionally I don't want to do anything to modify the vehicle itself within its warranty period. After that, and the kids (especially the younger one) has grown in size and proficiency, I won't mind tinkering with it a bit more.

I think for now buying the CR-1 and just keeping it plugged in all the time is the easiest and cost effective (considering time) option. But, I would like to plan my next move for a 2nd battery now so I can pull the trigger when needed:

I think at first, since I don't want to drill any holes or modify the wiring, the best bet is to just buy a 2nd 12V battery that I can swap out. I would like to buy one with as high an amperage as possible to maximize run time.

Because I don't want to modify the wiring, I think I will have to purchase a compatible wiring harness like this?

That will allow me to connect a 3rd party battery to the stock wiring, yes?

Then in another year, I can go ahead and put that battery in the hood and wire it in parallel with the stock battery for longer run time without switching.

And, if the kids are up to it I could then go ahead and wire them in parallel.

Does this sound like a reasonable plan?

Questions I still have:

1) I believe the stock battery is 12V 9.5 AH, but you can replace with a higher amperage for longer run time. Does anyone happen to know if there is a higher amperage battery (preferably 18 AH+) that would physically fit in the standard battery compartment?

2) When the time comes I should be able to use the stock 12V 9.5 AH with another 12V (series or parallel) regardless the AH, correct?

3) (For future thinking) I don't know much about those XLR ports shown in the video...but what do those plug into? Do you have to wire an XLR male connector onto a float charger?

4) I still have concerns about keeping the battery plugged in with a charging port AND charging at the same time. It doesn't seem safe to me that you would be charging the battery while it was still hooked up to the motor? Would you have to wire some sort of relay and/or key switch to make sure this wasn't a problem?

I will try my best to answer your concerns here and hopefully somebody else will charm in:

Because I don't want to modify the wiring, I think I will have to purchase a compatible wiring harness like this?

- This should work since I have this and it is working fine for me

That will allow me to connect a 3rd party battery to the stock wiring, yes?

- Yes

Then in another year, I can go ahead and put that battery in the hood and wire it in parallel with the stock battery for longer run time without switching.

And, if the kids are up to it I could then go ahead and wire them in parallel.

Does this sound like a reasonable plan?

- Yes people have done what you are planning to do above before including myself. However, if you are going to use aftermarket battery, then I would suggest using all aftermarket batteries if you are planning to connect these in parallel for consistency unless you are planning to buy another PW stock battery to put it in front and parallel connect the previous stock one with this one.

Questions I still have:

1) I believe the stock battery is 12V 9.5 AH, but you can replace with a higher amperage for longer run time. Does anyone happen to know if there is a higher amperage battery (preferably 18 AH+) that would physically fit in the standard battery compartment?

- For Dune Racer I think it's best for you to stick with 12AH battery since the 18AH version won't fit the back compartment (see specs below for dimension) I believe. For future plan, just hook up 2 12AH 12v batteries in back and front and you should have 24AH.

2) When the time comes I should be able to use the stock 12V 9.5 AH with another 12V (series or parallel) regardless the AH, correct?

- Need to stick with same AH for both battery. Most people here do 12AH battery in parallel

3) (For future thinking) I don't know much about those XLR ports shown in the video...but what do those plug into? Do you have to wire an XLR male connector onto a float charger?

- Similar to this:

4) I still have concerns about keeping the battery plugged in with a charging port AND charging at the same time. It doesn't seem safe to me that you would be charging the battery while it was still hooked up to the motor? Would you have to wire some sort of relay and/or key switch to make sure this wasn't a problem?

- You could have a toggle switch from the battery to the car and the charge port is directly connected to the battery for charging purpose I guess so when you flip the switch to off, there will be no current coming to the car from the battery but the charge port will still be active all the time.

Just one thing I would comment on. There is no need to go to all aftermarket batteries (to balance the Ah rating) for the two batteries if you are connecting them in parallel. This is because it's impossible to "overdischarge" one in this case without also overdischarging the other one, since they will always see the same voltage. The current draw will be different for the two -- roughly proportional to their capacities, and they will maintain roughly the same capacity (both will go to 70% full, then to 50%, then to 30%, etc.)

Your total capacity will simply be the sum of the two batteries.

(One caution: You should avoid connecting together a fully discharged battery with a fully charged battery; charge both separately initially, then hook them together and leave them together after that, even for charging -- you can charge them in parallel as well without any problems)

The balancing of Ah ratings is very important when connecting them in SERIES, because in that configuration both batteries have the same current draw. The 9.5Ah one will run out early but it's easy to over-discharge; if you are reading the voltage of the two batteries in series, you can get into a case where it shows 22V and you think it's fine, but it's 12.5V for one battery and 9.5V (fully/over-discharged) for the 2nd one.
This is why LIPO batteries have balance connections -- if you have a weaker cell, you need to be able to see it. You could run disparate capacities in series as long as you have measurements of them individually -- but in that case you're not really taking advantage of the best/largest battery.

lexx0116 wrote:
- For Dune Racer I think it's best for you to stick with 12AH battery since the 18AH version won't fit the back compartment (see specs below for dimension) I believe. For future plan, just hook up 2 12AH 12v batteries in back and front and you should have 24AH.

Thanks. I'm looking for the actual measurements of the battery compartment...otherwise I will be able to get them myself in about 2 weeks when we open the box. I thought the 18AH might be too large comparing it to the dimensions I found online for the stock battery, but it looks like I can probably find some 15AH ones that may work. If anyone has taken measurements and knows the exact dimensions of the inside, please share.

Hammer-fm wrote:Just one thing I would comment on. There is no need to go to all aftermarket batteries (to balance the Ah rating) for the two batteries if you are connecting them in parallel...

Thanks - this is the one thing I wanted clarification on because I though that this was the case for parallel wiring as you state.

The one additional thing I would like to know here is what would be the best way to continue to use the stock battery with an after market in parallel? How would I change my wiring from each using the stock PW wire harness (the stock having it built in, the aftermarket with the one above). If possible, I wouldn't want to modify the stock battery at all, but use another type of Y connector, but I'm not 100% sure how it would work.

I'm a bit confused as it looks from the diagrams I've seen that when you wire in parallel you have one wire going from the power source terminals to *EACH* battery's respective terminal. So you would need 4 wires coming from the power source for 2 batteries? Or can you wire from power source (+) > battery 1 (+) > battery 2 (+) and then do the same on the (-)?

Again, I don't plan on doing the parallel wiring probably for another year (unless there is a way I can do it that won't alter the original car)?